JD-U leader K.C. Tyagi told IANS that the party decided to support the Aam Aadmi Party because Kejriwal was "opposing the capitalist and communal nexus in this country".
Tyagi said he and JD-U president Sharad Yadav would campaign for Kejriwal in Varanasi where the third main candidate is Ajay Rai of the Congress.
Tyagi said the JD-U shared the anti-corruption plank of the AAP.
"Our party is a product of the JP movement. We fought against Indira Gandhi's corruption. Under V.P. Singh we fought against Rajiv Gandhi's corruption," Tyagi said.